Enhanced host–guest interaction between [10]cycloparaphenylene ([10]CPP) and [5]CPP by cationic charges

• Eiichi Kayahara,
• Yoshiyuki Mizuhata and
• Shigeru Yamago

Beilstein J. Org. Chem. 2024, 20, 436–444, doi:10.3762/bjoc.20.38

• will help tune the electronic properties of the host–guest complexes and design novel materials based on hierarchical supramolecular structures involving cyclic nanocarbons. Structures of a) [10]CPP⊃C60, (b) [n+5]CPP⊃[n]CPP, and (c) [10]CPP⊃[5]CPP2+ (this work). 1H NMR spectra (CD2Cl2, 25 °C) of a) a

Mono or double Pd-catalyzed C–H bond functionalization for the annulative π-extension of 1,8-dibromonaphthalene: a one pot access to fluoranthene derivatives

• Nahed Ketata,
• Linhao Liu,
• Ridha Ben Salem and
• Henri Doucet

Beilstein J. Org. Chem. 2024, 20, 427–435, doi:10.3762/bjoc.20.37

• from Acros. KOPiv (95%) was purchased from Doug Discovery. These compounds were not purified before use. All reagents were weighed and handled in air. All reactions were carried out under an inert atmosphere with standard Schlenk techniques. 1H, 19F and 13C NMR spectra were recorded on Bruker Avance

• data of synthesized compounds. Supporting Information File 44: Copies of 1H, 19F, and 13C NMR spectra. Acknowledgements We are grateful to Dr. Elsa Caytan for NMR experiments. Part of this work has been performed using the PRISM core facility (Biogenouest, Univ Rennes, Univ Angers, INRAE, CNRS, FRANCE

Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

• Eugeny Ivakhnenko,
• Vasily Malay,
• Pavel Knyazev,
• Nikita Merezhko,
• Nadezhda Makarova,
• Oleg Demidov,
• Gennady Borodkin,
• Andrey Starikov and
• Vladimir Minkin

Beilstein J. Org. Chem. 2024, 20, 336–345, doi:10.3762/bjoc.20.34

• 15N NMR spectroscopy (NMR spectra of compounds 4a–h, 5a–c, 6a,b, and 10c are given in Figures S13–S43, Supporting Information File 1), mass spectrometry (Figures S44–S56, Supporting Information File 1), IR and UV–vis spectroscopy, as well as elemental analysis. The NMR spectra were recorded on the

Spatial arrangements of cyclodextrin host–guest complexes in solution studied by ¹³C NMR and molecular modelling

• Konstantin Lebedinskiy,
• Ivan Barvík,
• Zdeněk Tošner,
• Ivana Císařová,
• Jindřich Jindřich and
• Radim Hrdina

Beilstein J. Org. Chem. 2024, 20, 331–335, doi:10.3762/bjoc.20.33

• signals in 13C NMR spectra. This signal split can be correlated to the distance of the guest atoms from the wall of the host cavity and to the spatial separation of binding sites preferred by pairs of prochiral carbon atoms. These measurements complement traditional solid-state analyses, which rely on the

• , we reveal the conformation (spatial arrangement) of the host–guest complex in solution spectroscopically by measuring the 13C NMR spectra of a suitable guest molecule. We decided to take Cs symmetric guest molecules, CD as a host and measure the 13C NMR spectra of these complexes. We expect that the

• anisotropy of the chiral cavity is expressed by differences in the magnetic shielding of prochiral atoms, resulting in signal splitting of the prochiral carbons of the guest molecule in 13C NMR spectra. Adamantan-2-amine hydrochloride was used as a model guest molecule containing three sets of prochiral

Discovery of unguisin J, a new cyclic peptide from Aspergillus heteromorphus CBS 117.55, and phylogeny-based bioinformatic analysis of UngA NRPS domains

• Sharmila Neupane,
• Marcelo Rodrigues de Amorim and
• Elizabeth Skellam

Beilstein J. Org. Chem. 2024, 20, 321–330, doi:10.3762/bjoc.20.32

• . The 1H and 13C NMR spectra of 1 revealed the presence of seven amide NH signals between δH 7.43 and 8.44 ppm supported by the amide carbonyl signals at δC 173.1, 172.6, 172.6, 172.1, 172.1, 171.1 and 171.0 ppm (Table 1). An additional NH signal at δH 10.82 ppm and four aromatic signals at δH 7.50

• , 7.33, 7.07 and 6.97 ppm, exhibiting key 1H,1H-COSY and HMBC correlations, suggested a tryptophan aromatic amino acid portion (Figure 3). The other six amino acid residues were assigned based on 2D NMR spectra (1H-1H COSY, HSQC and HMBC) as Ala (2 equiv), Phe (1 equiv), Leu (1 equiv), Val (1 equiv), and

• would like to thank Dr. Hongjun Pan for his kindness and teachings in the acquisition of NMR spectra as well as Jean Christophe Cocuron from the Bioanalytical Facilities (BAF) for HRMS data. Funding This project was supported by UNT Department of Chemistry and BioDiscovery Institute start-up funds, the

Unveiling the regioselectivity of rhodium(I)-catalyzed [2 + 2 + 2] cycloaddition reactions for open-cage C₇₀ production

• Cristina Castanyer,
• Anna Pla-Quintana,
• Anna Roglans,
• Albert Artigas and
• Miquel Solà

Beilstein J. Org. Chem. 2024, 20, 272–279, doi:10.3762/bjoc.20.28

• , leading to β-site isomers as minor products. Taking this into account, we carefully analyzed the NMR spectra of compound 2a. Analysis of 1H NMR spectra of 2a provided valuable information that confirmed the generation of two regioisomers in a 71:29 ratio (Figure 2). Comparable proportions of reactions at

Additive-controlled chemoselective inter-/intramolecular hydroamination via electrochemical PCET process

• Kazuhiro Okamoto,
• Naoki Shida and
• Mahito Atobe

Beilstein J. Org. Chem. 2024, 20, 264–271, doi:10.3762/bjoc.20.27

• . Electrochemical oxidation of 1 under varying conditions. Supporting Information Supporting Information File 18: Detailed experimental procedures, CV simulation, copies of NMR spectra. Funding This work was supported by JSPS KAKENHI (Grant Nos. 22K18915 and 21H05215 to M.A. and 22H02118 23K17370, and 23H04916 to

Nucleophilic functionalization of thianthrenium salts under basic conditions

• Xinting Fan,
• Duo Zhang,
• Xiangchuan Xiu,
• Bin Xu,
• Yu Yuan,
• Feng Chen and
• Pan Gao

Beilstein J. Org. Chem. 2024, 20, 257–263, doi:10.3762/bjoc.20.26

• )thianthrenium salt.a Supporting Information Supporting Information File 16: Experimental procedures, characterization data for all new compounds, and NMR spectra of products. Funding We are grateful for the financial support from the National Natural Science Foundation of China (22001227), the China

Substitution reactions in the acenaphthene analog of quino[7,8-h]quinoline and an unusual synthesis of the corresponding acenaphthylenes by tele-elimination

• Ekaterina V. Kolupaeva,
• Narek A. Dzhangiryan,
• Alexander F. Pozharskii,
• Oleg P. Demidov and
• Valery A. Ozeryanskii

Beilstein J. Org. Chem. 2024, 20, 243–253, doi:10.3762/bjoc.20.24

• 1:1 (Scheme 2). Complex 9 is insoluble in most organic solvents, but it turned out to be unstable in DMSO-d6 solution, as evidenced by monitoring its 1Н NMR spectra (Supporting Information File 1, Figure S1). Figure S1a shows the spectrum of the starting quinoline 5, Figure S1b represents complex 9

• results of 1H NMR spectra and TLC analysis, the second component was still present. This “permanent impurity” cannot be separated by chromatography or recrystallization, but it can be eliminated to some extent by washing the nitration products with hot chloroform, in which the impurity is slightly better

Optimizations of lipid II synthesis: an essential glycolipid precursor in bacterial cell wall synthesis and a validated antibiotic target

• Milandip Karak,
• Cian R. Cloonan,
• Brad R. Baker,
• Rachel V. K. Cochrane and
• Stephen A. Cochrane

Beilstein J. Org. Chem. 2024, 20, 220–227, doi:10.3762/bjoc.20.22

• Supporting Information Supporting Information File 12: Experimental procedures, characterization data, and selected copies of 1H, 13C, and 31P NMR spectra. Acknowledgements We extend our gratitude to Professor Alethea Tabor and Professor Stefan Howorka from University College London for their valuable

Comparison of glycosyl donors: a supramer approach

• Anna V. Orlova,
• Nelly N. Malysheva,
• Maria V. Panova,
• Nikita M. Podvalnyy,
• Michael G. Medvedev and
• Leonid O. Kononov

Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18

• after immersion in a 1:10 (v/v) mixture of 85% aq H3PO4 and 95% aq EtOH. 1H, 13C, and 19F NMR spectra of solutions in CDCl3 and acetone-d6 were recorded on a Bruker AVANCE-600 instrument at 600 MHz for 1H and 151 MHz for 13C or on a Bruker AM-300 instrument at 300 MHz for 1H, 75 MHz for 13C, and 282 MHz

• CFCl3 (δF 0.0). Assignments of the signals in the NMR spectra were performed using 2D-spectroscopy (COSY, HSQC, HMBC) and DEPT-135 experiments. For the copies of NMR spectra for all new compounds see Supporting Information File 1. High resolution mass spectra (electrospray ionization, HRESIMS) were

• anomeric ratio values (α/β, see Figure 2 and Table S1 in Supporting Information File 1). For determination of the α/β ratio, integral intensities of signals of α-H-3eq and β-H-3eq of Neu5Ac residue of 4 were used (for relevant parts of the 1H NMR spectra see Figures S1–S4 in Supporting Information File 1

Synthesis of the 3’-O-sulfated TF antigen with a TEG-N₃ linker for glycodendrimersomes preparation to study lectin binding

• Mark Reihill,
• Hanyue Ma,
• Dennis Bengtsson and
• Stefan Oscarson

Beilstein J. Org. Chem. 2024, 20, 173–180, doi:10.3762/bjoc.20.17

• choice [12], surprisingly better than a benzoylated donor [19], why this donor was the first one tested also with the quite different acceptor 5. An NIS/AgOTf-promoted glycosylation with donor 6 [20] yielded 79% of disaccharide 7. Due to the presence of rotamers, NMR spectra of 7 proved to be difficult

• , Reveleris® silica cartiges 40 μm, Büchi Labortechnik AG®) and Biotage® SP4 HPFC (UV 200–500 nm, Biotage® SNAP KP-Sil 50 μm irregular silica, Biotage® AB). Instrumentation 1H NMR and 13C NMR spectra were recorded on Varian Inova spectrometers at 25 °C in chloroform-d (CDCl3), methanol-d4 (CD3OD), deuterium

• oxide (D2O) or DMSO-d6 ((CD3)2SO). 1H NMR spectra were standardised against the residual solvent peak (CDCl3, δ = 7.26 ppm; CD3OD, δ = 3.31 ppm; D2O, δ = 4.79 ppm; (CD3)2SO δ = 2.50 ppm); or internal trimethylsilane, δ = 0.00 ppm). 13C NMR spectra were standardised against the residual solvent peak

Copper-promoted C5-selective bromination of 8-aminoquinoline amides with alkyl bromides

• Changdong Shao,
• Chen Ma,
• Li Li,
• Jingyi Liu,
• Yanan Shen,
• Chen Chen,
• Qionglin Yang,
• Tianyi Xu,
• Zhengsong Hu,
• Yuhe Kan and
• Tingting Zhang

Beilstein J. Org. Chem. 2024, 20, 155–161, doi:10.3762/bjoc.20.14

• conditions for the copper-promoted C5-brominationa. Supporting Information Supporting Information File 38: General information, experimental procedures for all the products, characterization data, and NMR spectra. Funding This work was supported by the National Natural Science Foundation of China (21801088

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• chemicals (Alfa, Merck, Fluorochem or BLDpharm) were of reagent grade and used without further purification. 1H NMR spectra were recorded with a JEOL ECZ 500 (1H: 500 MHz and 13C: 125 MHz) and a Varian VNMR S600 (1H: 600 MHz and 13C: 150 MHz) at T = 25 °C. The 1H NMR and 13C{1H} NMR spectra were referenced

• , additional spectroscopic data and 1H NMR spectra. Acknowledgements We thank Christina Böhringer and Sandra Uebach for technical assistance and Manuel Heinelt and Cristian Camilo Escobar Carranza for HRMS measurement (Department of Chemistry and Biology, University of Siegen). Funding Financial support by

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• Systems X10/X50: 40–63 μm). TLC was performed using aluminum sheets covered with silica gel coated with fluorescent indicator. NMR spectra were recorded on a Bruker instrument at 500 MHz and 126 MHz for 1H and 13C NMR, respectively. Deuterated chloroform (CDCl3, 1H = 7.26 ppm, 13C = 77.16 ppm), deuterated

• , see Figure 11). Supporting Information Supporting Information File 13: Synthetic protocols, UV–vis and NMR spectra, differential pulse voltammograms, and X-ray crystallographic data. Supporting Information File 14: Crystallographic information file of compound 25. Supporting Information File 15

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• similar phosphonium salt 2,4-di-tert-butyl-6-(triphenylphosphonium)phenolate features this particular signal at 6.27 ppm (4JHH = 2.7 Hz, 3JPH = 14.4 Hz [30]). In the 13C NMR spectra, the chemical shifts of the carbon atoms in positions 1 and 6 of the phenolate unit are particularly noteworthy. In the

• zwitterions formed to some extent (as evidenced by characteristic signals in the proton NMR spectra of the crude reaction mixtures) but could not be isolated in pure form. In case of methyl methacrylate, the reaction is accompanied by oligomerization of the Michael acceptor (Supporting Information File 1

• phosphorus signal for 2d). Stability tests were also performed in two different deuterated solvents, CDCl3 and DMSO-d6. No air or moisture exclusion was applied. The tests were performed at room temperature and at 60 °C. 1H and 31P NMR spectra of the solutions were taken after 24, 48 and 72 h. At room

Facile access to pyridinium-based bent aromatic amphiphiles: nonionic surface modification of nanocarbons in water

• Lorenzo Catti,
• Shinji Aoyama and
• Michito Yoshizawa

Beilstein J. Org. Chem. 2024, 20, 32–40, doi:10.3762/bjoc.20.5

• structure (DFT) of PA-CH3. b) Structures of PA-OCH3, PA-OH, and PA-Im. 1H NMR spectra (500 MHz, rt, 0.5 mM and 1.0 mM based on PA-CH3 and PA-OCH3, respectively, TMS in CDCl3 as external standard) of a) PA-CH3 in CD3OD, b) (PA-CH3)n in D2O, c) PA-OCH3 in CD3OD, and d) (PA-OCH3)n in D2O. DLS charts (rt, H2O

• )n and (PA-OCH3)n·(s-CNT or m-CNT)m, and g) (PA-OCH3)n and (PA-OCH3)n·(GN)m. 1H NMR spectra (500 MHz, D2O, rt, 0.5 mM based on PA-Im) of (PA-Im)n·(C60)m a) before and b) after addition of 40 equiv HCl. a) Protocol for the noncovalent encircling of g-C3N4 by PA-OCH3 and subsequent deposit of g-C3N4 on

NMRium: Teaching nuclear magnetic resonance spectra interpretation in an online platform

• Luc Patiny,
• Hamed Musallam,
• Alejandro Bolaños,
• Michaël Zasso,
• Julien Wist,
• Metin Karayilan,
• Eva Ziegler,
• Johannes C. Liermann and
• Nils E. Schlörer

Beilstein J. Org. Chem. 2024, 20, 25–31, doi:10.3762/bjoc.20.4

• data for publication, it also excels in enhancing teaching of NMR interpretation. In this paper, we present some current possibilities of this new tool. Several series of exercises are already provided on https://www.nmrium.org/teaching. Keywords: chemical education; E-learning; NMR; NMR spectra

• data in classes and exercises is usually based on a ‘static’ (i.e., printed/pdf-style) presentation of NMR spectra. No interactive data handling is possible, and manual annotations will typically be made during practicing exercises. Advanced approaches require the availability of locally installed

• of NMR data. While initially intended for small molecules data repositories and databases [34][35], NMRium provides unique functionalities that make it particularly well-suited for educational application. Teaching the interpretation of NMR spectra Nowadays, the interpretation of NMR experiments is

Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C,N-diheteroarylcarbamidines

• Pavel S. Silaichev,
• Tetyana V. Beryozkina,
• Vsevolod V. Melekhin,
• Valeriy O. Filimonov,
• Andrey N. Maslivets,
• Vladimir G. Ilkin,
• Wim Dehaen and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2024, 20, 17–24, doi:10.3762/bjoc.20.3

• embryo kidney cells (HEK-293), glioblastoma (A-172), and osteosarcoma (HOS) cells. Supporting Information Supporting Information File 25: Full experimental details and characterization data of all new compounds. Supporting Information File 26: Copies of NMR spectra of all new compounds. Funding Design

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• ) and 3-DAA (8), respectively, in a high conversion ratio. Comparison of cma and ava gene clusters.a Kinetic analysis of AvaA7. Supporting Information Supporting Information File 18: Additional experimental data and NMR spectra. Funding This work was supported by Grants-in-Aid for Scientific Research

1-Butyl-3-methylimidazolium tetrafluoroborate as suitable solvent for BF₃: the case of alkyne hydration. Chemistry vs electrochemistry

• Marta David,
• Elisa Galli,
• Richard C. D. Brown,
• Marta Feroci,
• Fabrizio Vetica and
• Martina Bortolami

Beilstein J. Org. Chem. 2023, 19, 1966–1981, doi:10.3762/bjoc.19.147

• spectrum) [106], we never detected such a peak in 19F NMR spectra of the neat IL, analysed after reaction work-up, keeping it under vacuum to completely eliminate diethyl ether traces before NMR analysis. It should be mentioned that the solution was kept in the NMR tubes only for the time necessary to

• record the NMR spectra. We cannot exclude that a much longer contact time between glass and solution could evidence such a signal. Using dried IL and adding 1 equiv of water with respect to alkyne (Table 1, entries 4 and 5), the yield of 2a improved from 53% to 72% after 5 h (Table 1, entry 1 vs 4), and

• -chelate. In fact, the following convincing peaks were found in the NMR spectra: a singlet at 6.11 ppm, along with a quartet at 4.68 ppm (1H NMR spectrum), a peak at 83.3 ppm (13C NMR spectrum) and a singlet at −139.1 ppm (19F NMR spectrum) [109]. A simple washing with distilled water gave the

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

• Nedra Touj,
• François Mazars,
• Guillermo Zaragoza and
• Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

• . Gratifyingly, this method allowed us to isolate the cross-conjugated mesomeric betaines 6c–f in good yields (Scheme 5). Clean NMR spectra were recorded in all cases, although elemental analysis revealed that the products were not entirely homogeneous. This might be due to the presence of inorganic impurities

• 1,2,3-triazolium dithiocarboxylate betaines under investigation. 1H NMR spectra of compounds 4a–c and 6a–f were rather similar to those of their precursors 3a–c and 5a–f, respectively, with only one less resonance due to the replacement of their acidic proton with a CS2 group (Table 1). Because the

• NMR spectra. Indeed, with values higher than 220 ppm, the chemical shift of a dithiocarboxylate unit is located in a spectral region where it can hardly be mistaken for anything else. On average, the δ CS2 value recorded for aldiminium inner salts 4a–c (229 ppm) was slightly higher than for triazolium

Construction of diazepine-containing spiroindolines via annulation reaction of α-halogenated N-acylhydrazones and isatin-derived MBH carbonates

• Xing Liu,
• Wenjing Shi,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1923–1932, doi:10.3762/bjoc.19.143

• methods. Because there are one C=C bond and one C=N bond in the molecules 3a–m, no diastereoisomers are obtained. Therefore, the 1H NMR spectra gave simple absorptions for the characteristic groups in the molecules. For further developing the scope of the [4 + 3] cycloaddition reaction, MBH esters of

• spiro[indoline-3,5'-[1,2]diazepine]-6'-carboxylates 5a–g in 63–77% yields (Scheme 3). The substituents on both substrates also showed little effect on the yields. The chemical structures were fully characterized by HRMS, IR, 1H and 13C NMR spectra. For demonstrating the synthetic value of this protocol

Beyond n-dopants for organic semiconductors: use of bibenzo[d]imidazoles in UV-promoted dehalogenation reactions of organic halides

• Kan Tang,
• Megan R. Brown,
• Chad Risko,
• Melissa K. Gish,
• Garry Rumbles,
• Phuc H. Pham,
• Oana R. Luca,
• Stephen Barlow and
• Seth R. Marder

Beilstein J. Org. Chem. 2023, 19, 1912–1922, doi:10.3762/bjoc.19.142

• , additional TD-DFT results, and NMR spectra of compounds. Funding This work was authored in part by the National Renewable Energy Laboratory (NREL), operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. This work was primarily

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• purification. Thin-layer chromatography (TLC) was performed using Merck Silica gel 60 F254 plates and visualized by UV (254 nm) fluorescence. Zeochem silica gel (ZEOprep 60/35–70 microns – SI23501) was used for column chromatography. 1H and 13C NMR spectra were recorded on a Bruker 400 spectrometer at 400 and

• NMR spectra. Funding This work was supported by the project of scientific co-operation program between Latvia, Lithuania, and Taiwan, "Synthesis and study of deep-blue TTF fluorescent emitters to exceed theoretical OLED external quantum efficiency reaching 15%" (grant LV-LT-TW/2023) and Research